Optical interconnection is attracting attention as technology for achieving higher speed, larger capacity, and lower power consumption in information transmission. Important element technology in optical interconnection is connection technology of optical wiring, and connections that are simple but provide high coupling efficiency are required not only for connecting optical fibers with each other but also for connecting optical wiring between boards, between chips, and within chips.
In connections of optical wiring, a connector connection using a connecting terminal called a ferrule is generally known, and configuring connectors to have multiple cores is essential in realizing connections of high-density optical wiring. As a conventional multicore optical connector, a known multicore optical connector is provided with: ferrules having positioning holes in which a plurality of end portions of optical fibers are arranged and a pair of guide holes into which guide pins are to be inserted; and the guide pins which are inserted into the guide holes of the ferrules to coaxially connect a pair of the ferrules (refer to PTL 1 below).
Meanwhile, an optical fiber with lens (an optical fiber collimator) in which a GRIN lens (a gradient index lens) is fused to a tip of an optical fiber is known (refer to PTL 2 below). A connection of optical wiring using an optical fiber with lens has features that enables energy density of emitted light to be reduced due to beam expansion by a GRIN lens and, at the same time, enables connecting end faces to be mutually contactless. When the energy density of emitted light is reduced, a phenomenon where a connecting end face or an interior of an optical fiber is damaged by generation of heat caused by energy concentrating on a foreign object adhered to an end face, a fiber fuse associated with the generation of heat, or the like can be avoided, and further by making the connecting end faces contactless, optical coupling can be performed even when a foreign object is present on a connecting end face and the trouble of cleaning the connecting end face or the like can be spared. Furthermore, in a connector connection, making connecting end faces contactless prevents scuffing or defects from occurring on a ferrule end face.